再生细骨料保温混凝土抗压强度试验研究

Experimental study on compressive strength of recycled aggregate thermal insulation concrete

对6种不同再生细骨料取代率的再生细骨料保温混凝土进行抗压强度试验,并依据试验作出其抗压强度正态分布概率密度曲线,分析混凝土抗压强度及其变化特点。研究表明:再生细骨料取代率不超过80%时,混凝土7 d及28 d抗压强度随着再生细骨料取代率的增大而提高,7 d、28 d抗压强度最大分别为33.1、35.4 MPa;7 d抗压强度标准差基本稳定在1.65±0.3 MPa,取代率对其影响较小;28 d抗压强度标准差随取代率的增加而增大,且在取代率为20%时,标准差为3.34 MPa,符合GB/T 50107—2010及JGJ 55—2011中对最小标准差的规定,应按实测值标准差确定。

Six different kinds recycled fine aggregate substitutive ratio of recycled fine aggregate thermal insulation concrete （RATIC） are tested on compressive strength,meanwhile normal distribution probability density curve is obtained on the basis of the test to analyze the compressive strength of RATIC and its characteristics of change. Research shows that when the recycled fine aggregate substitutive ratio is less than 80%,7 d and 28 d compressive strength of RATIC increase with recycled fine aggregate substitutive ratio increasing, the maximum compressive strength of 7 d and 28 d is about 33.1 MPa and 35.4 MPa respectively. The standard deviation of 7 d compressive strength is stable at around 1.65±0.3 MPa and the substitution rate has little influence on it. The standard deviation of 28 d compressive strength increases with the growth of substitutive ratio,and when the substitutive ratio is 20%,the standard deviation is 3.34MPa. It is able to meet the minimum demand of GB/T50107-2010 and JGJ 55-2011 for the standard deviation,so the standard deviation can remain the same as it is actually measured.